Device for maintaining the slack of cinematographic films



S. KUCHARSKI.

DEVICE FOR MAINTAINING THE SLACK 0F CINEMATOGRAPHIC FILMS.

APPLICATION FILED MOI/.28, 1919.

1,395,119. Patented 001 25,1921.

v v I INVENTEIR B 9 11AM,

1 5V ATI'D'RN 6/ 0 provided for restoring urra sra'ras 'PTENT OFFICE.

STANISLAUS. KUCHARSKI, 0F CHABLOTTENBURG, 7 TO RICHARD A. I-IANSEMANII, OF

NEAR BERLIN, GERMANY, ASSIGNOR BERLIN, GERMANY.

Application filed November 28, isle.

Z '0 all who-m z'tmay concern Be it known that I, STANISLAUS KUoHaR- SKI, engineer, a citizen of Germany, residing at andwhose posteoflice address 1s Char- 5 lottenburg', near Berlin, Dernburgstrasse 45, Germany, have invented certain new and useful Improvements in Devices for Maintaining the Slack of Cinematograplnc Films, of which the following is a specificatlon.

This invention relates to a device fpr maintaining the correct amount of slack in cinematographic films near the focal plane of the lens of automatically operating apparatus for displaying moving pictures.

In automatic cinematographs in which a slack portion of film band is maintained behind the window through which the moving pictures are projectec, it may happen that the slack becomes so short as to prevent the injured film band from being pulled on stepby-step in the proper manner. The ob ect of the invention is to provide a dev ce for preventing an impermissible shorteningof the slack. In accordance with the lnventlon the device is arranged to automatically pull forward a certain amount of film to make up for any said shortness of slack, and to thus constantly maintain the slack at the proper length. The device by which this is accomplished consists of a member which, on the slack being unduly shortened, is auto matically brought by the partially tautened film into engagement with a moving part and caused to exert a pull upon the film band so as to draw forward the length required to make up the correct amount of slack.

A manner of carrying out the invention is shown in the drawing in which- Figure 1 shows a View of the slack regulating device and Fig. 2 is a side view as seen from the left of Fig. l.

The film band a is drawn forward so as to provide a store of slack 0 before the window Z) and another piece of slack (Z behind this window, the latter piece being continually kept at a certain length by the motion imparted to it by the roll 6. A means is this piece of slack to the required length in case it is unduly shortened, this means consisting of a roll f arranged within the reach of the slack (Z and journaled in an arm 9 which is piv- 5 oted to the frame at the point it. The arm Specification of Letters Patent.

Patented Oct. 25, 1921. Serial No. 341,207.

g is provided with a: projection or an angle piece in. The d lies beneath the path traversed by a pin Z, which is attached to the shaft m. The shaft m is an intermediate shaft which serves to transmit the motion of the motor a to the roll e which performs the double function of pulling one part of the film band away from, and/feeding another part of ittoward, the window of the apparatus. The shaft 9* is driven from motor at and by means of a cam-disk 8, causes oscillations of alever u that is pivoted at t and that imparts its oscillationsrto a seizing member a which shifts the picture band step-by-step past the picture window. 7

i As long as the slack cl of the film is suffic ently long the arm 9 remains in the po- Slt1OI1 Sl1OWI1 in the drawing and in which the pin Z attached to the rotating shaft m passes over the dog 2' as indicated in Fig. 1. But if the allowance of slack (Z becomes too dog 2' will seize the d the angle is, thus swinging forward the arm 9, which has an articulation at some point between its two ends, say at P, where its two hinged portions are normally forced apart by a spring 0 so as to form a certain angle. The roll 7 is thus caused to exert a pull upon the slack portion (Z of the film and to cause the normal length of slack to be restored and to maintaln the pictures at the window in their correct positions. The upper side of the angle piece is lays itself upon the pin Z so as to prevent a premature dropping of the arm 9 and enable sufiicient film to be pulled forward to restore the slack to its full length be1f1o;e the pin Z releases the arm 9 with the re I claim:

1. In combination with a self-acting apparatus for displaying moving pictures, a film band, a window, means for moving one portion of the film band toward, and another portion away from the said Window, While providing a certain amount of entering slack before, and a certain amount of issuing slack beyond, the Window, a driving member, and a slack-lengthening member shifted by the issuing slack into engagement with the driving member when the length of the issuing slack is unduly shortened.

2. In combination with a self-acting apog 2' usually.

paratus for displaying moving pictures, a film band, a window, means for moving one portion of the film band toward, and another portion away "from the said window, while providinga certain amount of entering slack before, and a certain amount of issuing slack beyond the window, a source of power, a shaft rotated by the said power, and a pin carried by said shaft, a frame,

a slacklengthemng member comprising an arm arranged, to press against the issuing slack, and a dog attached to the said arm, and movable joints allowing the dog of the slacklengthening member to be lifted by the issuing slack into the range of the rotating pin andpermitting the slacklengthening member to press against, and exert a pul upon, the issuing slack.

3. In combination with a self-acting apparatus for displaying moving pictures, a film band, a window, means for moving one portion of the film band toward, and another portion away' from, the said window, while providing a certain amount of enteringslack before, and a certain amount of issuing slack beyond, the window, a source of power, a shaft rotated by the said power, and a pin carried by said shaft, a frame, a slacklengthening member comprising an arm arranged to press against the issuing slack and a dog attached to the said arm, movable joints allowing the dog of the slacklengthening member to be lifted by the issuing slack into the range of the rotating pin and permitting the slacklengthening member to press against, and exert a pull upon, the issuing slack, and a means attached to the said dog for maintaining said slacklengthening member in a lifted position until a sufiicient lengthening of the issuing slack has been accomplished. In testimony whereof I have afiixed my signature'in presence of two witnesses.

STANISLAUS KUCHARSKI.

V Witnesses:

PAUL MASGOW, PAUL GALDA. 

